Measure the incidence of the maxillary sinus membrane perforation during the Osseodensification crestal sinus grafting procedure.

Retrospective clinical study to :

1. Investigate maxillary sinus membrane perforation incidence via osseodensification crestal sinus grafting utilizing the Densah bur.
2. Assess the osseodensification technique efficacy for maxillary crestal sinus grafting with implant site preparation.
3. Study and analyze the maxillary sinus perforation rate during or post-Osseodensification-mediated sinus grafting as a function.
4. To share the knowledge from this retrospective analysis through scientific publications.

Inclusion Criteria:

1- Medically healthy patients treated with crestal sinus augmentation via osseodensification using the Densah Burs and implant placement.

Exclusion Criteria:

1. History of radiotherapy,
2. Bisphosphonate medication.
3. Active periodontal disease.
4. Uncontrolled diabetes.
5. Heavy smoking (> 20 cigarettes/day).
6. Local acute apical abscess.

Medically healthy patients older than 21 years old who are treated with crestal sinus augmentation via osseodensification using the Densah Burs and implant placement.